Credit card holders need to be extra vigilant about fraud on accounts they no longer use. Cash has learnt of a number of recent cases where banks have continued to send out cards and Pins even after being informed that the card holder has moved.

Mike Addelman and his partner Sarah contacted Cash last week after spending three years trying to stop MBNA sending them mail intended for the previous occupant. 'We moved into our house in Sale [near Manchester] about three years ago, and the previous occupants' mail was still being sent to our address. A lot of that was from MBNA, so we called and asked them to stop sending it, which they said they would - but this never happened.'

Addelman says the couple called MBNA on numerous occasions and were on the phone for an average of 40 minutes each time. They returned more than 50 envelopes to the bank saying on them that the account holder was no longer at the address. 'In the end we opened up some of the mail and there was a lot of very detailed information about the account holders in there. We also received blank credit card cheques, two credit cards and, in a separate mailing, the account holder's Pin with a letter saying a new credit limit of £15,000 had been granted. We think this is appalling and shows that they are not taking the security of their customers seriously. We cannot be the only people this has happened to.'

MBNA apologised to the couple and has now closed down the previous occupant's account. 'Anyone receiving an MBNA credit card would have to pass stringent security procedures to activate the card before it could be used,' a spokesman said. 'In addition, consumers would not be liable for any fraudulent transactions that may occur on an account.'

Two weeks ago Cash received a letter with a similar tale from a reader in London who was fed up after spending eight months contacting Barclaycard to tell them to stop sending him mail intended for the previous occupant, the account holder. This time the reader was sent six credit card statements, a credit card and a Pin number. Barclaycard apologised and sent the reader £25 in compensation but could not explain why no one had acted on the reader's calls.

Another reader emailed to say he had settled his credit card account and then moved house, unaware that a new credit card was sent to his old address and subsequently used to make fraudulent transactions. The credit card company passed the debt to a debt collection agency, which is now pursuing him for payment.

Figures from the Association for Payment Clearing Services (Apacs) show fraud losses for 'mail non-receipt' - where a card never reaches its recipient - had risen by more than 60 per cent from £45m in 2003 to £72m in 2004, the year when most chip and Pin cards were issued. The latest statistics, however, show this falling to £40m last year.

'The big driver for card-not-present fraud is when someone forgets to notify their bank that they've moved or where there is a communal hallway,' says Jemma Smith, spokeswoman for Apacs. 'The cases [above] were obviously caused by administrative errors on the part of the card companies and sound highly unusual. The card holder would not be liable for any fraud that did occur in these cases.'

But incidents of identity fraud, where a criminal uses a fraudulently obtained card or card details to open or take over a card account in someone else's name, continue to grow year on year, accounting for £30m of losses last year. According to credit reference agency Experian, almost half of all identity theft happens at a previous address.

An account that has not been used for some time is often declared dormant by a card issuer, but there is no set time limit in which this has to be done. Halifax, for example, says if an account hasn't been used for 12 months prior to the bank reissuing a card it will write to the card holder and ask them if they want the new card. Barclaycard, on the other hand, used to operate a 'three-year rule' when deciding whether an account was dormant or not. It has since changed this so that cards issued from October 2004 will become dormant if there is no activity on them for 21 months.

Apacs is also warning card holders to be extra vigilant about checking the statements they do receive. Although official figures for the first half of this year are not available until next month, it says early indications are that fraud at ATMs is on the rise, after having fallen by 12 per cent for the first time last year. 'This is due mainly to gangs continuing to do old-style skimming fraud at cash machines and taking stolen details abroad,' says Smith.

Sainsbury's Bank announced last week that it is to spend £3.5m on security around its 885 cash machines after worries about increasing levels of fraud in this area. 'Without a doubt chip and Pin has had a positive effect on overall levels of fraud but in this area [ATMs] the problem seems to be growing,' says Kevin Barrett, head of channels at Sainsbury's bank. 'We do twice as many transactions at our ATMs than on average cash machines, so we're being proactive with this move, not reactive.'

The new measures will include changing the position of CCTVs within the supermarkets, attaching 'anti-skimming' devices to all its ATMs and a number of more low-tech solutions, such as putting a line on the ground around ATMs to make it clear that the area is a private space.

How to fight back

What you should do if you receive financial post for a previous occupant?

· Contact the bank and ask to speak to customer services. If you have no luck there, try the customer relations manager.

· If the card issuer ignores repeated requests to stop sending you somebody else's mail, you can take your complaint to the Financial Ombudsman Service. The FOS would not be able to take it on as a formal complaint as it is not your account, but it has had some success in the past when it has made informal contact with credit card companies over this problem.

· If you open someone else's mail, technically you are committing a criminal offence. Under the Regulation of Investigatory powers Act 2000 it is an offence to open, destroy, hide or delay any post that is addressed to someone else, even if you know that it has been incorrectly delivered.

What you should do to protect yourself against fraud?

· Notify all your card issuers if you change address - even for those accounts you no longer use

· If you no longer intend to use a credit card, close down the account, don't just cut up the card. Cutting up a card or putting it in a drawer doesn't shut down the credit facility.